Brake-control-valve mechanism



Feb. 8 1927.

N. A. CHRISTENSEN .A BRAKE CONTROL VALVE MECHANISM I Filed July l9, 1926BRAKEEVL//YUE/Q.

Hlllll 5MM@ 7' A T TORNE YS Patented Feb. 8, 1927.

valves, morevparticularly adapted for use AUNIT-151D Vs'raijlas1,616,571 'PATENT OFFICE.

NIELS CHBISTENSEN, OF CLEVELAND, OHIQ.

BRAKE-CONTROL-VALVE MECHANISM.

Application led July 19,

The invention relates to brake control in connection with theiiuid-pressure-operated brakes of automotive vehicles and trailers forsuch vehicles. j

The object of this invention is to provide an improved "control valvemechanism in which the brakingl pressure of the system may be readilycontrolled by the operator of the vehicle so that said pressure may bereadily varied by the operator to secure the desired brake applicationpressure, the control vbeing Vmore particularly designed for footoperation. More spectically the object of the invention is to provideimprovements over the typejof control valveshown in my copendingapplication, Serial No. 23,847,

Afiled April 17 1925.

The invention further consists 1n. the

several lfeatures hereinafter described and more particularly pendedclaims.

In the drawings, 'Fig'. an elevation view ofbrake-control-valve"iiiechanism embodying the inventiomshowing itapplied to an automotive vehicle 5 Y Fig. 2 is a vertical -sectionalview of the. valve mechanism embodying the invention;

Fig. '3 is a viewl to Fig. 2 showing a modified form of parts o themechamsm.

-pointed out in the ap.

Referring to Figs. l and 2, `the numeral 5 designates a valve casinghaving a space 6 formed therein, including a bore 7. A passage 8, avalve-controlled exhaust 'pas- Sage 9 and a valve-controlled inletpassage 10 communicate with thespace 6. A relief valve 11 controls theow of air or other pressure luidfrom the 'space 6 to the passage 9 andthence in a compressed air system to atmosphere, and anl inlet valve 12controls the flow of compressed air or pressure fluid from a chamber 13connected by a pipe 14 with the reservoir 15. The. passage 8 isconnected by any suitable piping 16 to the brake cylinders 17 associatedwith the Wheels ofthe vehicle.

The inlet valve has a tubular `portion18 I slidably mounted in the bore''of a box-nut 19 having threaded engagement with the casing, and has ahead 20 of composition material inset therein and held yagainst the seat21 by a spring 22 mounted'in the bore ofthe portion 18 and interposedbetween the end of said bore and the outer end of the bore in the nut19.

i926. seriai No. 123,570.

i A push-pin 23 is slidably mounted in the passage 10 and has a stemportion 24 mounted in a'bore lin a lug 25 of the casing. The

head 2 6 of thislpin engages the head 2() of 'i the inlet'valve 12 andis tapered so as /to' gradually increase the eli'ective port op/ening'asit is'puslied inwardly by the pperating means.`

-A piston 27, formed of parts 28 and 29 and the liexible 'packing 3U,Works in the bore 7 and has a rod portion 31 slidably mounted in gui-deand cover plate 32 secured to the casing. 'lhe outer end of this rod 3lworlis in a tubular extension 33 or' the plate 32 which has a verticallydisposed slot 34 -therein in which the operating lever 35 Works. 'lhislever 35 is secured intermedinormally held aty one side of its pivotagainst a ulcruni provided by the rounded head 'or a screw 3( by meansoi' a tension spring 33 secured at one end to the upper Vend or thelever 35 and adjustably connected ate its ends to the rod 3l by a pin 36and vis alined with the bore in-end portion 43, the i bore 44 being ofsmaller diameter than the bore 45 to yform a stop liange 46. t

'lhe relief valve l1 is in the form of a poppet needle'type valvehaving` the conical head adapted to seat on the inner end of the passage9 and having a tubularste- With a flange 47 and a bore 48. A4 spri l49is mounted in the bore 48 and interposed between the end of said boreandthe inner {end of the bore in end portion.43, and:said

'spring normally acts to move the valve 11 so that its ange 47 abutsagainst the liange' 46. Thus the valve 11 is moved by and/ with thepiston 27 through the pressure'of vthe spring 49 and the piston 27 vmayalso move relative to said valve-when it seats. The valve 11 is notresponsive to theairpressure in the space 6 to effect its openin but its`change in position is, due directy to the position and movement of thepiston 27.

The casingis provided with a ange 5() for convenient mounting on thedash 51 of the vehicle by clamping bolts 52 and the spring 38'worksthrough aah-ole 53 in the dash,

The modification shown in.Fig.'2 is generally similar except for thetype of piston vor pressure-responsive member and the parts `11 to 26`are the same in construction and operate the same as parts 5 to 26previously described. The piston 27 vconsists of' the parts28 and 29 anda multiple diaphragm 30 secured at one end in aJ fluid-tight man# ner,as by soldering, to the flange on the inner side of the part 29" and atitsother end 32 to 49, inclusive, are similar to in a similar manner tothe cover plate 32.

The relief valve 11 isvmounted in the part 29, which is similar to thepart'29, and is .the lever .or 35 the piston'27 or 27.

is moved inwardly, therebyincreasing the tension of the spring 38, andthe irst effect of this movement eausesthe exhaust valve 411 or 11vto-be moved to its seat to close oft the exhaust passage 9 or 9.Further inward movement puts pressure upon the valve 11 or 11 throughthe compression of the spring 49 or 49 land then causes the piston toengage the pin 24 or 24and moveit to open theinlet valve 12 or 12',whereupon the com# -pressed air from the reservoir flows from the Ipipe14, chamber 13 or 13', passagelO or 10 to the space 6 or 6 and thencethrough the passage 8 or 8 and pipes 16 to the brake cylinders 17. Asthe pressure in the bra-ke system builds up,the. pressure in the space 6or" 6 in front of the piston 27 or 27 increases luntil it overcomes the.pressure being exerted by the operator throu h the spring 38 wherevuponthe piston trave s away from the stem 24 01H24', due to the change ofthefulcrum from screw '37v to the pedal portion of the lever and the inletvalve closes and the parts'- are then in a lap position, since thepistontravel is then' not suilicientto relieve the pressure on the spring 38to such an extent as to permit unseatinglof the'valve 11 or 11',

which, it will be noted, has a greater tendency to remain seatedbecauseof the diii'erent-iai areas of the seat and the valve. Thereafterrelease of the increased tension on the spring 38 by the release ofpressure on the pedal will cause the piston 27 or 27 to travel outward,due to the pressure exerted upon it by the'conipressedfluid in the space6 or 6 Vand to the initial -tension of. the spring 38 so thatfinally-the piston moves to thel po-v s ition shown in the drawingwherein the ref lief valve-is open, with a consequent exhaust of airfromthe bra-ke system, or further pressure is desired a further increase oftenv greater movementl sion' in the spring 38 by a. ofthe pedal lever bythe operator will cause the piston 27 or 27 to move fromthe. lapposition heretofore noted tov again engage the pin 24 or 24 `and causethe inlet valve 12 or 12 to be again opened to admitmmore remainsclosed.

Thus, the more the operator presses down upon the-brake pedal 35 or 35the greater is the force stored up in the spring 38 and the lgreater theair pressure in the space 6 or 6- vair fromv the reservoir while thevrelief valve v has to be to overcome this force to bring the.

valves to a lap position so that the extent ofibraking pressure in thesystem is dependent upon the degree of movement of the lever 35 or 35whichis under the control of the' operator, the amount of brakingpressure he desires. Furthermore, the lap position is obtained throughthe shifting of the ulcrum' point between the screw 37 and thefoot oftheoperator since each of these points has a lostl motion associationwith the pedal which 'permits the piston to be moved either by the` whocan thus regulate and control operator or by the compressed air withinthe valve mechanism against the tension of the spring 38.- f

In case the spring 38 should break or get out oforder, I- have provideda limiting stop- `screw 54 mounted on a yoke fsecured to the cover platein any suitable manner, as

by the screw37, so as to limit the outward movement of the piston andperm-itoperation ofthe valve without the compensating action untilrepairs can be made.

`Oli course, it will be understood that the pin 24 or. 24 may be formedintegral withthe valve 12 or 12. f A

I desire it to be understood that this invention is not to be limited toany particular form'or arrangement of parts except-n so far as suchlimitations are speciiied in the claims.

What I claim as my invention is;4

1. AIn brake control mechanism', the combination of acasingcommunicating with -the` brake system and having inlet and exhaustports, an inlet valve controllin the passage of motive Huid through'saidlnlet port to said `casing and brake system,'an exhaust valvecontrolling the release of, fluid 'from v said casing and brake systemthrough Said exhaust port, a piston working in said oas ing for openingsaid mletvalve and respon- Vsive to the pressure in said casing, saidexhaust valve being carried by and having a 'i yieldable connection withsaid piston whereby the piston moves independently of said exhaust valveto open said inlet valve or to permit its .closing` when said exhaustvalve lever upon which and from which said lever is free to shift underthe varying tensions of saidl spring incident tothe operators pressureupon said lever and the pressure in the brake system.

2. In brake control valve mechanism, the combination of a casingcommunicating With a spring-close inlet valveiior said inlet p'ortopened-by the piston, a'spring-pressed exhaust valve for said exhaustport carried and closed by the piston, an operating lever' pivotallyconnected to said piston and having a pedal portion, a springassociated` with said piston and lever,and a fulcrum member for saidlever on the zopposite side of said lever from said pedal portion, saidlever adapted to fulcruin about said fulcrum member or about said pedalportion through v a change in pressure in the brake system.

3. In a vehicle control valve, the combination of a casing communicatingWith the brake system and having inlet ports, an inlet valve for saidinlet port, apiston Working in said casing for opening said inlet'valve, a spring-pressed exhaust valve carried by the piston and movablerelative thereto topermit said piston to open said inlet valve or moveto a lap .position `when said exhaust valve is closed, said pistonbeingmoved in an outward direction by fluid-pressure in said casing, springmeans for resisting the entire movement of saidv piston Vby saidpressure and for movin it .inthe opposite direction, a foot pedalplvoted to said piston and' associated with said spring means and underthe control of the operator for varying the pressure of said spring,land ,a fulcrum for said lever against which it abuts when the pressureexerted upon said. lever 'by the operator exceeds the pressure in thebrake system and from Whlch said lever is free to movevvhen the brakepressure exceeds the operators pressure upon said lever.

4. In a vehicle control valve, the combination with a casing havinginlet and exhaust ports, 'inletfand exhaust valves therefor, avalve-operating member carrying and having movement relative to saidvexhaust valve, a foot pedal .pivotally associated with said member andhaving a shiftable fulcrum, and a spring resisting movement of saidmember by the pressure in said brake system and of said pedal br theoperator.

5. In a ve tion/"ftvith a casing having inlet and exhaust ports, poppetinlet and exhaust valves for said ports, a pressure-responsive memberadapted to open said inlet valv and 4upon which said exhaust valve iscarried and with respect to which it has relativemovement and includinga multiple bellows diaphragm whereby said member ismovable to a lapvposition While exerting a 'closing pressure ,ipon said exhaust valve,said member being responsive to `changes in pressurev in the brakesystem, and operator-controlled means for actuating saidmember.

In testimony whereof, I aiix my signature.

umts A. oHRrsTENsEN.

y "cle control valve, the combi'na-`

